Siege of Massilia (258 BC)

The Siege of Massilia occurred in 258 BC when a 530-strong Roman army under Vibius Julius, having just taken the city of Massilia, was besieged by the 222-strong Gaulish army of Togodumnus of Lacus Lemannus. The Romans sallied forth and attacked the Gauls, decisively defeating them in battle and destroying their army.

Background
In the winter of 259 BC, the Roman general Vibius Julius captured the city of Massilia (Marseilles, France) from Dumnorix and his army of Gauls. The Romans enslaved 1,406 Gauls and dispersed them throughout the rest of the Roman Republic, and the Romans intended to move north to conquer the rest of Gaul. However, they were faced by several Gaulish armies in southern Gaul, and Togodumnus of Lacus Lemannus and his army of 222 Gauls laid siege to the Roman army in Massilia. The Roman garrison decided to sally forth, as Vibius Julius carried his House of Julii pride forward and decided to fight the enemy on an open field.

Battle
The Roman army of 530 troops exited the city of Massilia to engage the 222-strong Gallic army on the plain in front of the field. The Gauls moved to the west, taking up position along some elevated ground; the Romans deployed on the plain below. In the ensuing encounter, the Romans used their Gaulish mercenary cavalry to charge the Gaulish warbands, massacring them; their hastati then charged in and fought the weaker barbarians. The Gauls were slaughtered, losing 150 men; the Romans lost 50 men. Vibius Julius won a great victory, and a barbarian turncoat joined his retinue after the decisive victory.